Nukes as a nifty source for hydrogen in the future
■"Hydrogen Production Method Could Bolster Fuel Supplies," by Matthew L. Wald, New York Times, 28 November 2004, pulled off web http://www.nytimes.com/2004/11/28/politics/28hydrogen.html?oref=login.
U.S. government researchers “say they have found a way to produce pure hydrogen with far less energy than other methods, raising the possibility of using nuclear power to indirectly wean the transportation system from its dependence on oil.”
Three things hold up the hydrogen economy: 1) how to produce hydrogen cleanly and without excessive cost, 2) shipping it and storing it on vehicles, and 3) reducing the cost of fuel cells, which for now remain awfully expensive. This technology possibly solves #1, if American can get over their fear of nukes.
Just any old nukes? No, a different nuclear generation technology than the one we are used to and which produced gems like Three Mile Island and Chernobyl.
The best way to get hydrogen is to use electricity to separate water into its components (taking the H out of the H2O). But if you use coal to generate the high-temp water required, then you use lotsa energy to yield a lesser amount of energy, plus you create all that CO2. So what if you could produce very high-temp water as a byproduct of nuclear power generation?
Traditional nuclear reactors use water for cooling and generate water heated only in the range of 300 degrees Celsius, but scientists believe they can build a different type of reactor, one that employs helium gas as the cooling medium, that can achieve super-hot temps of 1,000 degrees Celsius. That hot gas would be used to move turbines to generate electricity and to super heat water to roughly 800 degrees. Put some of that electricity together with the hot water and presto! You’ve got hydrogen.
But when do we get this new helium gas-cooled nuclear reactor? Unclear.
The point made by the advocates of Pebble-Bed Modular Reactors, which use large numbers (360,000 or so) of small pellets of graphite-coated uranium oxide, is that this method is good for generating that sort of heat using a technology that is decades old and very robust in terms of safety and immunity from proliferation dangers.
So the question these advocates ask is, Why not go with something we know can work now rather than wait on some fabulous technological breakthrough? At least that’s a question some researchers at M.I.T. are asking.
You have to wonder if our ever-present and always-exaggerated fears of nuclear proliferation are getting the best of us. To me, PBMR sounds like a Gap-shrinking technology worth pursuing now.